seal

[1]	seal off/up , close (off/up) , shut (off) , zip up , plug (up) , stop (up) , lock , bolt , secure , batten down , make airtight/waterproof , cork
[2]	authenticate , confirm , verify , validate , affirm , attest , ratify , clinch , corroborate , assure , ensure , guarantee , endorse
[3]	seal off
[4]	varnish

[1]	symbol , sealing wax , token , mark , insigne ((plu , ) insignia) , sign , signet , crest , bearing , coat of arms , escutcheon , emblem , badge , monogram , identification , cartouche , design , imprint , stamp
[2]	authentication , stamp , confirmation , verification , validation , affirmation , attestation , ratification , corroboration , assurance , guarantee/guaranty , endorsement , substantiation , evidence , notice , notification
[3]	sealskin
[4]	Navy SEAL
[5]	cachet , seal of approval